Ugly Face Build

build your own Ugly Face!

Ugly Face

Ugly Face is a racus squarewave guitar synth oscillator disguised as a fuzz pedal.

Originally created by Tim Escobedo on his Circuit Snippets web page, it’s become a DIY classic. The ideas here are great and inventive there are a lot of building blocks. Out of all of these the Ugly Face leaps out at your like a rabid warthog. 

The board here was design in Eagle PCB. The pots and LED are mounted to the board for easy assembly. Get boards at: https://oshpark.com/shared_projects/BldK2X8b

Notes: Solder parts to boards without the LED or pots. Drill your box with the guide at the end of this document. Fit the pots and LED in the board without soldering. Mount the pots into the enclosure with the nuts and washers. Then fit the LED through the hole. Now solder the legs of the pots and LEDs. 

NOTE! I found an issue with the ground connection on the output side. It’s not connected to the group plane! Otherwise everything works.

PartValue
C122µ
C21n
C3100n
C42µ2
C5100µ
C6470n
C7100n
D12N5817
D2LED
EnvelopeB1K
FrequencyA50K-A100K
ThresholdB10K
VolumeA100K
R11M
R2470
R3100K
R422K
R51K
R61K
VACTAny LED/LDR pair will work
5557555
LM386LM386
Ugly Face Parts List
Ugly Face Schematic